Microsoft codenames are the codenames given by Microsoft to products it has in development, before these products are given the names by which they appear on store shelves. Many of these products (new versions of Windows in particular) are of major significance to the IT community, and so the terms are often widely used in discussions prior to the official release. Microsoft usually does not announce a final name until shortly before the product is publicly available. It is not uncommon for Microsoft to reuse codenames a few years after a previous usage has been abandoned.

There has been some suggestion that Microsoft may move towards defining the real name of their upcoming products earlier in the product development lifecycle so as to avoid needing product codenames.[1]

Although this release was still 16-bit Windows, it included a 32-bit TCP/IP stack (when running on compatible hardware). Along with Win32s, this was one of the first steps towards moving the Windows desktop to a 32-bit code base.

Cancelled upgrade for Windows 95; sometimes referred to in the press as Windows 96. Codename was reused for Internet Explorer 4.0 and Windows Desktop Update which incorporated many of the technologies planned for Nashville.

Went gold (RTM) on 8 of November 2006. Named after the Longhorn Bar in the Whistler-Blackcomb resort; initially planned as an "interim release" between "Whistler" and "Blackcomb" (which was "Vienna" and is now Windows 7).

Supposedly a family of multi-core technologies including an operating system, applications and development tools designed to make better use of today's multi-core CPUs. Midori may be a part of this suite of new Microsoft technologies.

"Monads", according to philosopher Gottfried Leibniz's monadology, are the ultimate elements of the universe, individual percipient beings, and MSH is similarly composed of small, individual modules the user puts in interrelation.

Internet Explorer 1, first shipped in Microsoft Plus! for Windows 95: The codename O'Hare ties into the Chicago codename for Windows 95: O'Hare International Airport is the largest airport in the city of Chicago, Illinois — in Microsoft's words, "a point of departure to distant places from Chicago".

Project Lightning was the original codename for the Common Language Runtime in 1997. The team was based in building 42, hence Project 42. "Next Generation Windows Services" appeared in the earliest press releases about the upcoming platform.

Roslyn is the next generation of design guidelines for developer tools, which is often highlighted by a C# compiler being written in C# (currently it is C++) and being offered as a service. This would enable scenarios like C# having its own version of the JavaScripteval command ultimately leading to meta-programming. Mono has had a similar feature since early on its life.

Jasper provides a data programming interface for rapid application development. When a Jasper program runs, Jasper connects to the database, determines the database schema, and generates corresponding data classes. This generation step does not occur in source files; rather, the data classes are compiled in memory and are only available for use within the running program.

"Stimpy" was merged into "Ren", which was later became "Wren". "Ren" and "Stimpy" are references to Ren and Stimpy, characters of an American animated television series. "Wren", a homophone of "Ren", is a reference to Christopher Wren, the architect of St Paul's Cathedral.

An online content-authoring platform centered around the concept of distributed Object Linking and Embedding (OLE) and meant to be an alternative to HTML. The developer tools were originally released in beta and some titles were made available on MSDN before it was scrapped in favor of web development around ASP and ActiveX and the designer was refashioned into Visual InterDev.

Aims to: define higher-level abstractions (above "threads and locks"); for today's imperative languages; that evenly support the range of concurrency granularities; to let developers write correct and efficient concurrent applications; with lots of latent parallelism; that can be efficiently mapped to the user's.

Effort to develop a small, very secure operating environment within Windows, including curtained memory, trusted input, and graphics. Project renamed to Next-Generation Secure Computing Base, and was never fully implemented.

^Russinovich, Mark; Solomon, David A. (2005). Microsoft Windows Internals (4th edition ed.). Microsoft Press. p. xx. ISBN0-7356-1917-4. The first release of Windows NT was larger and slower than expected, so the next major push was a project called Daytona, named after the speedway in Florida. The main goals for this release were to reduce the size of the system, increase the speed of the system, and, of course, to make it more reliable.